Well-chosen words - FT.com: Why is English spelling such a tangle? It all started when Latin-speaking missionaries arrived in Britain in the 6th century without enough letters in their alphabet. They had 23. (They didn’t have “j”, “u” or “w”.) Yet the Germanic Anglo-Saxon languages had at least 37 phonemes, or distinctive sounds. The Romans didn’t have a letter, for example, for the Anglo-Saxon sound we spell “th”. The problem continues. Most English-speakers today have, depending on their accents, 40 phonemes, which we have to render using 26 letters. So, we use stratagems such as doubling vowels to elongate them, as in “feet” and “fool”.
With the Norman invasion in 1066, spelling became more complicated still; French and Latin words rushed into the language. As the centuries went by, scribes found ways of reflecting the sounds people used with the letters that they had. They lengthened vowels by adding a final “e”, so that we could tell “hope” from “hop”.